Pixel Me This

Description

How does a satellite, whether spinning directly above Earth or deep in space, get the information it has collected back down to us so that it can be of use? When a satellite sends a message to Earth, that information is carried along on radio waves. The information carried on those waves comes piecemeal, a little bit at a time, incredibly fast. That information is then received, aggregated, and interpreted by computers and the scientists that use them.

In this activity, students will begin to understand how radio waves travel across a distance to bring information from its source, the satellite, to its target, the one collecting the data.

Adapted from Communicating into Space: The Sky’s No Limit, from National Science & Technology Week 1997

Materials

Graphing paper, 1 sheet per student

Crayons/ colored pencils: blue, red, brown, yellow, orange, and green

Name tags

Eight slips of paper, each one with a single word from this sentence: “Roger, mission control. We are ready for landing.”

Optional: Colored beads, corresponding with the colors available as crayons/ colored pencils

Outline- Introduction

1.      To introduce students to the concept of transmissions through space, choose one student to be “Mission Control,” and give them a name tag saying so. The educator will be the “Space Shuttle,” also with a name tag stating so.

2.      Stand several feet apart. One at a time, the educator/ Space Shuttle will toss the slips of paper with the message, one word at a time. Having caught the paper, the student will read the word out loud to the class until the entire message has been transmitted.

a.      Optional: Have a third student, “Scientist,” record the message on the whiteboard as it comes in.

3.      Remind students that this happens much faster in real life: radio waves travel at the speed of light, and Hubble is sending them much faster than the educator is tossing paper. But it isn’t just spoken words that can be sent: images can, too.

Outline- Main Activity

1.      Distribute a sheet of graph paper to each student and give them the crayon/ colored pencils in the colors listed under “materials.” Have them label the grid with numbers 1-11 across the top, and letters A-G down the side. The boxes can be as large or small as they want, so long as they all have the same 1-11/A-G grid

2.      Now, the students will be both Mission Control and the Scientists, receiving and recording the messages. The educator is now the “Hubble Space Telescope” with a new name tag.

3.      The educator/ Hubble will call out different colors in the sequence of the above chart. As they do so, students should fill in their grid one box at a time, from left to right, up to down. When they reach A11, they will move to the next row to B1, and so on until the grid is filled. Stop periodically to make sure everyone is on the same grid square.

4.      Once the colors have all been called, have students compare their grids. What message did they spell out? (ANSWER: Hi)

Extended Activity

·        Select a new student to be “Mission Control,” while the educator remains the “Hubble Space Telescope.” Instead of reading the colors aloud, Hubble will toss colored beads to Mission Control, who will say the color out loud to the class. This can either replace the original, spoken-only activity, or the educator can create a new message if “Hi” has already been done.

·        Have students work in small groups and develop their own color-coded message. Have each group trade their message with another and see if the new group can successfully decode it.

·        Go outside and increase the distance between participants. Having the students toss beads over a greater distance translates to at least some beads being dropped: don’t pick them up! Consider this a “lost” part of the message. Compare results.

·        Similar to above, but mix students up in a large “cloud.” Can they still keep track of their message when there are others flying around them? This emphasizes the need for proper tuning/ being tuned to the correct “station” when receiving messages.